Abstract: The scientific literature, which suggests numerous circuits built with approximate 4-2 compressors, has a lot of interest in approximation multipliers. The designer who desires to employ an approximation 4-2 compressor faces the difficulty of selecting the suitable topology due to the enormous variety of available alternatives. This paper compares approximate 4-2 compressors already proposed in the literature in this work. We also introduce a fresh approximate compressor, bringing the total number of approximate 4-2 compressors studied to twelve. The circuits under investigation are used to create 8x8 and 16x16 multipliers in 28nm CMOS technology.
Keywords: Multiplier, 4:2 Compressor, Half adder, full Adder.